Problem with geterrmessage()

If the script detects presence of a particular file USERCODE.txt, it executes:
source(“USERCODE.txt”)
If that file is not present, the script executes without a problem.

There might be syntax errors in USERCODE.txt; therefore, the code above is embedded in a try command:
try(source(“USERCODE.txt", local=T), silent=T)
followed by:
ERRORMESSAGE <- geterrmessage()

For unclear reasons, an earlier command is yielding an error message:
unused argument (\"\\n\")
Despite identifying the exact source of that error, I can’t fix it (and it is of no consequence).

Ideally, I would like to clear out the pre-existing error message immediately before the “try” command (or perhaps at that particular location where it is being created) — but I can’t figure out how to do so.

Re: Problem with geterrmessage()

Only the default error handler puts the error message in a buffer
where it can be retrieved with geterrmessage. try() replaces the
default error handler. Either look at the value returned by try() or
use tryCatch with conditionMessage.

Best,

luke

On Thu, 22 Feb 2018, Dennis Fisher wrote:

> R 3.4.3
> OS X
>
> Colleagues
>
> I have a 20K line script in which I encounter an unexpected problem.
>
> If the script detects presence of a particular file USERCODE.txt, it executes:
> source(“USERCODE.txt”)
> If that file is not present, the script executes without a problem.
>
> There might be syntax errors in USERCODE.txt; therefore, the code above is embedded in a try command:
> try(source(“USERCODE.txt", local=T), silent=T)
> followed by:
> ERRORMESSAGE <- geterrmessage()
>
> For unclear reasons, an earlier command is yielding an error message:
> unused argument (\"\\n\")
> Despite identifying the exact source of that error, I can’t fix it (and it is of no consequence).
>
> Ideally, I would like to clear out the pre-existing error message immediately before the “try” command (or perhaps at that particular location where it is being created) — but I can’t figure out how to do so.
>
> Any suggestions would be welcome.
>
> Dennis
>
> Dennis Fisher MD
> P < (The "P Less Than" Company)
> Phone / Fax: 1-866-PLessThan (1-866-753-7784)
> www.PLessThan.com
>
> ______________________________________________
> [hidden email] mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html> and provide commented, minimal, self-contained, reproducible code.
>

Re: Problem with geterrmessage()

Please read ?try (again) carefully.In paticular note (under Value):

"The value of the expression if expr is evaluated without error, but an
invisible object of class "try-error"containing the error message, and the
error condition as the "condition" attribute, if it fails."

so:

attr(ERRORMESSAGE, "conditon") will give you the error conditon.

Cheers,
Bert

Bert Gunter

"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )